U.S. Pat. No. 4,153,326 (which is hereby incorporated by reference in its entirety) discloses and claims a wiring system in which hermaphroditic type electrical connectors are used to connect the ends of wires in a first cable to the ends of wires in a second cable. The connector shown in this patent is not only hermaphroditic but it also can be mated with an identical connector which is in opposed inverted relationship to the connector on the end of the first cable. This feature is important in connectors used for service wiring systems, for the reason that corresponding wires, for example, color coded wires, in the two cables will be connected to each other when two of the connectors are coupled to each other. The connector shown in U.S. Pat. No. 4,153,326 can also be coupled to other complementary connecting devices, such as tap connectors installed on a cable intermediate the ends thereof.
It would be desirable to provide a latching means on connectors of the general type shown in U.S. Pat. No. 4,153,326 to latch two connectors to each other upon coupling, thereby to prevent accidental de-coupling with a resulting interruption in electrical service. Integral latching means on multi-contact electrical connectors are widely known and are commonly used in the electrical industry. Presently available latching systems are not, however, suitable for connectors used in modular wiring systems for several reasons. For example, it is highly desirable that the connectors be hermaphroditic so that only one type of connector is required throughout a wiring system. Furthermore, it is not sufficient that the connectors be merely hermaphroditic; the connectors must also be such that corresponding wires in two cables be connected to each other when two connectors are coupled to each other. For example, the ground wire in the one cable must be connected to a ground wire in the second cable, and the connectors must be such that it is impossible to incorrectly connect the wires in two cables to each other.
Known types of connector latching systems are not entirely satisfactory for modular wiring applications for the additional reason that it is frequently necessary to couple and de-couple the connectors under awkward or unfavorable conditions, such as when the connectors are located in relatively inaccessible portions of a wiring installation. A satisfactory latching system for connectors used in service wiring systems must therefore be such that connectors can be coupled and de-coupled quickly and conveniently under such adverse conditions. Additionally, the latching means used should be positive and relatively foolproof so that wiring cables can be installed by a relatively unskilled technician and, after installation, will remain coupled under all normal expected circumstances.
The present invention is therefore directed to the achievement of an improved connector having improved latching means for use on cables used in modular wiring systems for buildings or the like.
A preferred form of electrical connector in accordance with the invention comprises an insulating housing of molded thermoplastic material having a mating end, a conductor entry end, oppositely facing sidewalls, and oppositely facing endwalls extending between the two ends. Latching means are provided on each of the endwalls, each latching means comprising a latch arm and a latching ear. The latch arms are disposed on one side of a medial reference plane which extends through the connector normally of the endwalls and substantially bisects the endwalls. The latching ears are on the other side of the reference plane so that two connectors in opposed inverted relationship can be coupled to each other. The resulting connector assembly, comprising the two coupled connectors, is thus held together by four latch arms, two latch arms on each side of the connector assembly. The latch arms are provided with conveniently located finger pieces that can be grasped by a technician who wishes to de-couple the two connectors under unfavorable or adverse circumstances, such as where the connectors are inconveniently located.